The present invention relates to solid-state imagers, and more specifically to solid-state imagers fabricated in conformity with the standards of a high picture quality television system.
Presently, Japan, the United States and many other countries employ the NTSC television system using a total of 525 scanning lines. The newly developed high picture quality TV system such as EDTV or HDTV, on the other hand, requires about twice as many lines as the NTSC system. Conventional solid-state imagers having pixel formats corresponding to the NTSC system are utterly incompetent for the EDTV or HDTV. Recently, research and development are being made to realize and improve imagers at the level of definition of the ED or HD system.
New imagers adapted to the EDTV or HDTV system are not readily used for the NTSC system. One way is to convert a picture signal of a new imager into a picture signal of the NTSC system by performing interpolation in the horizontal scanning period with a down converter. This technique, however, cannot provide a video camera capable of producing picture signals of both television systems by itself. In such a state of art, it is required to produce solid-state imagers on two different standards at the cost of production efficiency.